1. Field
One embodiment of the invention relates to a technology for supplying power to a device and, more particularly, to an information processor that supplies power to a device via a bus.
2. Description of the Related Art
Recent information processors such as a personal computer (PC) are provided with an interface for connection to other devices. Examples of the interface include a universal serial bus (USB) (registered trademark) and bus interfaces according to a standard such as IEEE 1394. The information processors are capable of supplying power to a device connected thereto through such a bus interface.
For example, Japanese Patent Application Publication (KOKAI) No. 2006-53748 discloses a conventional technology in which, even if the power is off or in power saving mode, an information processor starts supplying power to a device when the device is connected thereto via a bus interface.
It is not always the case that every time a device is connected to the bus interface, the information processor is capable of supplying power to the device through the bus interface. More specifically, it is not enough to simply connect a device to the bus interface because each device is supplied with power or is chargeable in a different condition. Therefore, it is necessary to specify the setting of the USB controller, power source circuit, or the like of the information processor to be suitable for a device connected thereto.
Generally, this setting is specified by selecting a setting suitable for the device from a plurality of settings with a predetermined tool such as a utility program installed in advance on the information processor. This means that the user is required to determine a setting to be selected for a device that the user has connected to the bus interface to charge the device.
If the user has recharged the same device a plurality of times, the user can determine the setting allowing the device to be rechargeable from experience. However, if the user charges a device for the first time, it may be difficult for the user to specify a setting to be selected to charge the device. In this case, the user has to select a plurality of settings one by one and repeatedly try charging the device with each selected setting to determine the one suitable for the device.